Limb Deficiency

Limb deficiency can be defined simply as the loss of a part of a limb. It can be congenital (present at birth) or acquired. It can present as complete or partial loss. In a transverse deformity all the elements of the limb are absent at a certain level. In a longitudinal deformity there will be complete or partial absence of some elements with other elements intact. For example, one of the forearm bones, the radius, may be missing while the other forearm bone, the ulna, may be intact.

Common Causes of Limb Deficiency

There can be a number of causes:

• Agents causing physical defects in a foetus e.g. thalidomide
• Amniotic banding where fibrous bands from the sac surrounding the foetus, form a tight band around a developing limb causing amputation
• Severe infections e.g. meningococcal
• Surgical amputation to treat malignancy
• Accidents

Management of Limb Deficiency

Prosthetic devices (“artificial limbs”) are prescribed if there is complete absence of a limb. Upper limb devices work best when introduced very early because it becomes an integral part of the child’s body during development.

Where there is malformation and some remaining function especially in an upper limb, this residual function must be respected as children can achieve surprisingly good function despite marked deformity and sometimes using unorthodox movements.

Where there is marked deformity, lack of function or pain, cosmetic amputation may be considered. This would then produce a neat stump to facilitate the fitting of prosthesis. This type of situation could occur following trauma.

Physiotherapists and occupational therapists supervise prosthetic training, advise on adaptive equipment especially for the upper limb, monitor on-going use of the prosthesis, monitor and facilitate normal motor development, and provide advice to schools etc. Those with lower limb deficiency may require mobility aids such as crutches and wheelchairs to maintain independence in all situations.

Lower limb prostheses are fitted at the time of normal walking development. Lower limb prostheses are generally well tolerated except where there are high-level above-knee amputations. In this case, the energy expenditure to walk is high and the child may prefer partial use of a wheelchair. Where there is a single below-knee amputation, these children can have near normal function.

The compliance with upper limb prostheses is highly variable. Limb fitting commences as early as six months and increasingly sophisticated prostheses can be introduced as the child matures. The huge disadvantage compared to a normal hand is that the prosthesis does not have sensation hence the child may prefer to sometimes use the stump to manipulate objects. Others often transfer some functions to the feet especially where there is two-handed deficiency.

In Queensland, Queensland Amputee Limb Service runs clinics for prescription and repairs, and these are based at major hospitals. MontroseAccess can offer therapy support through out teams. Additionally counselling may be required from time to time.